I'm sorry, but I really don't see the distinction you're drawing here. Art, especially writing, is pure profit once you've paid for the materials. If you choose to make a dime a day at it, it's still profit.
Great works of art may, of course, be produced while the artist starves. That does not mean that starving is a necessary precondition to art, nor does it mean that eating is not a necessary precondition. It means that the artist has found a means other than art to support him- or herself.
Profit and professionalism aren't necessary in making automobiles, either - you could certainly make a case that some very fine stuff is produced by highschool mechanics working in their spare time. If you restrict the automobile world to only such individuals by denying profit, however, I don't think it would be a gain overall either in terms of the quality or the quantity of the autos produced. So with art.
I disagree. Labor is a real cost of doing business. Almost all businesses would be insanely profitable if they didn't have to pay employees.
In one of my examples above, I pointed out that James Joyce spent something like 50,000 man hours writing Finnegans Wake, made about $3,000 from it and was surprised to have received that much.
No one rationally sets out to spend almost two decades to do a job which they expect will pay them less than six cents an hour.
It is, as they say, a labor of love.
My point is, again, that truly great creative accomplishments are not products of cost/benefit analysis.
I agree that starving or physical suffering is not a necessary precondition for great art: TS Eliot lived a very comfortable existence as a successful merchant banker, while producing great art - often during his free time on very posh vacations.